New principle may help explain why nature is quantum

May 14, 2013
A principle of 'accepting the facts' implies that a quantum bit (typically pictured as a 'Bloch ball') can look like a sphere but not like a polyhedron. Polyhedral bits have been linked to theories of discrete spacetime. By ruling out various alternative theories of nature, the principle may help to explain why the world is quantum. Credit: Timothy Yeo / CQT, National University of Singapore

Like small children, scientists are always asking the question 'why?'. One question they've yet to answer is why nature picked quantum physics, in all its weird glory, as a sensible way to behave. Researchers Corsin Pfister and Stephanie Wehner at the Centre for Quantum Technologies at the National University of Singapore tackle this perennial question in a paper published today in Nature Communications.

We know that things that follow quantum rules, such as atoms, electrons or the that make up light, are full of surprises. They can exist in more than one place at once, for instance, or exist in a shared state where the properties of two particles show what called "spooky action at a distance", no matter what their . Because such things have been confirmed in experiments, researchers are confident the theory is right. But it would still be easier to swallow if it could be shown that quantum physics itself sprang from intuitive underlying principles.

One way to approach this problem is to imagine all the theories one could possibly come up with to describe nature, and then work out what principles help to single out quantum physics. A good start is to assume that information follows

Einstein's and cannot travel faster than light. However, this alone isn't enough to define quantum physics as the only way nature might behave. Corsin and Stephanie think they have come across a new useful principle. "We have found a principle that is very good at ruling out other theories," says Corsin.

In short, the principle to be assumed is that if a measurement yields no information, then the system being measured has not been disturbed.

accept that gaining information from quantum systems causes disturbance. Corsin and Stephanie suggest that in a sensible world the reverse should be true, too. If you learn nothing from measuring a system, then you can't have disturbed it.

Consider the famous Schrodinger's cat paradox, a thought experiment in which a cat in a box simultaneously exists in two states (this is known as a 'quantum superposition'). According to quantum theory it is possible that the cat is both dead and alive – until, that is, the cat's state of health is 'measured' by opening the box.

When the box is opened, allowing the health of the cat to be measured, the superposition collapses and the cat ends up definitively dead or alive. The measurement has disturbed the cat.

This is a property of in general. Perform a measurement for which you can't know the outcome in advance, and the system changes to match the outcome you get. What happens if you look a second time? The researchers assume the system is not evolving in time or affected by any outside influence, which means the quantum state stays collapsed. You would then expect the second measurement to yield the same result as the first. After all, "If you look into the box and find a dead cat, you don't expect to look again later and find the cat has been resurrected," says Stephanie. "You could say we've formalised the principle of accepting the facts", says Stephanie.

Corsin and Stephanie show that this principle rules out various theories of nature. They note particularly that a class of theories they call 'discrete' are incompatible with the principle. These theories hold that quantum can take up only a finite number of states, rather than choose from an infinite, continuous range of possibilities. The possibility of such a discrete 'state space' has been linked to quantum gravitational theories proposing similar discreteness in spacetime, where the fabric of the universe is made up of tiny brick-like elements rather than being a smooth, continuous sheet.

As is often the case in research, Corsin and Stephanie reached this point having set out to solve an entirely different problem altogether. Corsin was trying to find a general way to describe the effects of measurements on states, a problem that he found impossible to solve. In an attempt to make progress, he wrote down features that a 'sensible' answer should have. This property of information gain versus disturbance was on the list. He then noticed that if he imposed the property as a principle, some theories would fail.

Corsin and Stephanie are keen to point out it's still not the whole answer to the big 'why' question: theories other than quantum physics, including classical physics, are compatible with the principle. But as researchers compile lists of principles that each rule out some theories to reach a set that singles out , the principle of information gain versus disturbance seems like a good one to include.

Explore further: Scientists find way to maintain quantum entanglement in amplified signals

More information: "An information-theoretic principle implies that any discrete physical theory is classical", Nature Communications, doi: 10.1038/ncomms2821 (2013) Preprint available at http://arxiv.org/abs/1210.0194

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cardzeus
3.2 / 5 (9) May 14, 2013
Terrible example. 'If you look in the box and find the cat dead then making a second measurement you wouldn't expect to find the cat resurrected' - but what if your initial measurement showed the cat to be alive? Then why would you expect a second measurement to show the same??
hemitite
5 / 5 (3) May 14, 2013
Would it be possible then to disturb a system without to some degree measuring it?
Claudius
2.9 / 5 (17) May 14, 2013
According to quantum theory it is possible that the cat is both dead and alive


It would have been more accurate to say "According to one interpretation of quantum theory..." In a many-worlds interpretation, the cat is not both alive and dead until the box is opened. The cat is alive in one world and dead in another, and you are merely finding out which world you are observing from when you open the box.
snoosebaum
1.3 / 5 (15) May 14, 2013
seems silly, must be a narrow definition of measure, as one can measure with ruler ,scale ,etc? without disturbance.
krundoloss
2 / 5 (7) May 14, 2013
I feel that all the quantum weirdness is attributed to things popping in and out of existance (our dimension). It could certainly explain the concept of "Quantum Superposition" , because much like the blades of a fan, if you stick a pencil in the area where the blades are spinning and remove it in a very small amount of time, you may or may not hit the fan blade. I think these small particles are the same way, changing state or pulsing constantly, and if you measure it you are changing it (much like the pencil hitting the fan blade and affecting its motion). Im just a layman, but it makes sense that things are so strange in the quantum world because its not made up of real matter, but merely the pulsing of matter into and out of our dimension.
EyeNStein
1.8 / 5 (16) May 14, 2013
The whole article shows woolly thinking.
Any interaction between a one system and another system represents information exchange.
That second system may well be a measuring photon or other 'particle'. The disturbance to both systems then depends on the properties of BOTH the system being measured and the type of measurement you chose to make. This much was already known.

This article doesn't seem to add to the sum of human knowledge. Except that it ( IMO correctly) disregards the anthropic view that observers create the universe, or multiple universes exist for each interaction.

Though they do fall into the standard pitfall that that cat is both alive and dead just because someone put it in a box with a contraption with a quantum trigger. Where in fact the cat is just as valid an observer of the device going off as the person opening the box.
EyeNStein
1.6 / 5 (14) May 14, 2013
krundoloss
If you instead imagine it as two fans with blades with their arcs intersecting you would be nearer the truth: They may or may not interact at a given point in time or space.
This is more like the wave particle duality which is found experimentally.
Both fans are like waves while sweeping through space and time, unmeasured and undisturbed, until they collide and their interaction is described like particles.
You could say the second fan is making a measurement.
ValeriaT
1.8 / 5 (10) May 14, 2013
The whole article shows woolly thinking
You're right. Maybe the reading of the original article will make the discussion less woolly.
Like small children, scientists are always asking the question 'why?'
Some scientists are apparently more childish than others (like Feynman).
An information-theoretic principle implies that any discrete physical theory is classical
This is indeed a nice sentence - but what does it mean? Is such sentence testable? Do we have some discrete physical theory? Are quantum mechanics or general relativity discrete theories? Which theory such a sentence is supposed to apply?
no fate
3 / 5 (4) May 14, 2013
seems silly, must be a narrow definition of measure, as one can measure with ruler ,scale ,etc? without disturbance.


A quantum system can only be measured by inputing or extracting information via photon exchange (currently). Adding or subtracting the energy of one photon has an effect on the system due to its size. It is the narrowest definition of measure outside the subatomic.
EyeNStein
1.5 / 5 (15) May 14, 2013
"An information-theoretic principle implies that any discrete physical theory is classical"
They seem to be using the principle that the discrete bit of information is the most important conserved quality in the universe. However they would be very hard pressed to explain the information exchanges of QED as a classical phenomenon. The quark transformations of weak-force interactions would have puzzled Isaac Newton greatly.
Tektrix
1.8 / 5 (5) May 14, 2013
"Adding or subtracting the energy of one photon has an effect on the system due to its size."

By *its*, do you mean the photon or the system? Regardless though, I agree in principal- I think :)

If a photon has only one quanta of energy, and to measure this photon requires the exchange of at least one quanta between the photon and the observer, isn't the quanta associated with the photon "used up" for this exchange of information, thus removing the photon from 'existence' (its quanta becoming associated with a different quantum system?) Destroying the photon sounds like a pretty serious disturbance from a photon's perspective. Assuming the foregoing then, if you don't have this exchange, then no information is exchanged and thus the photon is not disturbed.
Higgsbengaliboson
1.8 / 5 (5) May 14, 2013
Quantum gravitational theory-it correlates with Einstein's theory of relativity(both general and special) which would enable us to relate with the article published here.Schrodinger's cat is a probabilistic phenomena i.e we can only know the cat's health once the box is open s.t quantum particles are associated in a discrete state rather than a smooth continuous way.
Eikka
3.4 / 5 (11) May 14, 2013
Where in fact the cat is just as valid an observer of the device going off as the person opening the box.


So are every air molecule in the box besides the cat. You're confusing observing with concious observing, when it really means just propagation of effects from causes.

Outside of the box, the scientist has not yet felt the effects of the cat being dead, regardless of whether the cat feels himself dead or alive, so what the cat observes is in a superposition to the scientist as well, and the scientist is in superposition to his supervisor who hasn't yet heard of the results of the experiment, etc. etc.
Torbjorn_Larsson_OM
3.9 / 5 (7) May 14, 2013
This is interesting, since we have good reasons to believe discrete and/or quantum fluctuating spacetimes don't work. At least the discrete ones has no energy gap, no lower energy, and so can't make harmonic oscillators so has no dynamics. And supernova photon timing shows that spacetime is perfectly smooth beneath Planck scales.

On the other hand it is not really telling us why we see quantum physics in the first place. But analogous to above, a simple probabilistic model shows that classical physics is discrete, have a discrete mapping of in to out state, while quantum physics is continuous in that sense. (Also seen in how we can take systems partly in and out of decoherence.)

And QM happens to be the smallest dimensional such physics (2D probability map instead of 1D classical) - it minimizes hidden variables and visible parameters both.

[Various refs, takes too long to dig them out for a short comment. The supernova is SN1987, IIRC.]
Torbjorn_Larsson_OM
4.3 / 5 (6) May 14, 2013
Also of note is that they disregard weak measurements (they don't need them), which observes over ensembles in a statistical sense.

@cardzeus: Yes, as it says the system is assumed not evolving in time. You are thinking of resuming the experiment.

@hemitite: It seems they say no.

@Claudius: And actually Shroedinger was showing how the classical Copenhagen and instrumentalist theories becomes absurd, see EyeNSteins comments. It is, in this sense too, a terrible example.

@snoosebaum: Observation (measuring) is fundamental in quantum mechanics. "The framework of quantum mechanics requires a careful definition of measurement." [ http://en.wikiped...echanics ]

It isn't measuring in classical sense, but with interaction with a quantum system.
Torbjorn_Larsson_OM
4.3 / 5 (6) May 14, 2013
@krundoloss: What do you mean with quantum weirdness and "things popping in and out of existance"? The likelihood for a quantum fluctuation popping some substantial "thing" in and out is very small, on the order of the lifetime of the universe after heat death or so.

Virtual particles on the other hand are just impermanent illdefined unnatural disturbances in a quantum field allowed by the energy principle under quantum physics (eg Heisenberg's uncertainty relations), while particles are more or less permanent (in comparison) welldefined natural ripples. [ http://profmattst...re-they/ ] Virtual particles are hence easy to fluctuate, but they aren't really "things", have no real mass (in fact mass comes out as a complex number IIRC, if you try to calculate it, so very much "not real" =D) et cetera.
TheGhostofOtto1923
1.5 / 5 (12) May 14, 2013
Terrible example. 'If you look in the box and find the cat dead then making a second measurement you wouldn't expect to find the cat resurrected' - but what if your initial measurement showed the cat to be alive? Then why would you expect a second measurement to show the same??
Yes of course... the cat would be dead but its little cat spirit would still be alive somewhere in outer space. Problem solved.
kriminy
1 / 5 (2) May 14, 2013
when does weak measurement become destructive?
Moebius
1.4 / 5 (9) May 14, 2013
The 'why' of quantum physics is beginning to sound spiritual. Or vice versa.
EyeNStein
1.8 / 5 (14) May 14, 2013
kriminy.
As weak measurements are probabilistic: The more certain you are of your measurement, the more probably disturbed the system is.
In the famed twin slit experiment: The wave interference pattern on the screen fades in proportion to how certain you are of a weak measurement made of the particles approaching the slits.
javjav
1 / 5 (1) May 14, 2013
I feel that all the quantum weirdness is attributed to things popping in and out of existance
No, that is due to the Heissemberg principle, which is the easier part of Quantum mechanics. To me the quantum weirdness is more about other examples like the particle entanglement (spooky action at a distance) or the double slit experiment with measurement delayed in time (where a future decision seems to affect a past event).

Regarding the article I don't agree, in such a system we could force the appearance (or impede it) of new particles from the outside that will interact with the old ones even if we do not make any measurement we will disturb the system.
I mean, if we open the box and we throw a dog into the box without looking at the cat and we close the box then we have not measured anything and we haven't got any information, but we may have disturbed the system a little bit isn't it?
EyeNStein
1.8 / 5 (16) May 14, 2013
Moebius
The big debates of physics have always had a spiritual dimension.
From Einstein's "God does not play dice" to the huge row between Gamov and Hoyle over the big bang creation event.
As ultimate physics becomes more uncertain and probabilistic; and every concrete classical concept like space and time becomes less invariant: Many will invoke or revoke God depending on their personal leanings.

Myself I have no problem accepting that conscious life could be an emergent property of the 'bulk space' our 'brane' universe and its time and space came from: Just as conscious life is an emergent property in our Universe. We just cant prove it either way with our current knowledge.

Its the folk who get all definitive and shouty, without any humility, nor thinking stuff through, who cause all the loudest arguments.
Ober
1.1 / 5 (7) May 14, 2013
What I don't understand is the following;
Consider an un-measured entity has not collapsed its wavefunction and can therefore be in many states at once. You now measure the entity and cause it to collapse, taking on a definitive state. How does this collapsed wavefunction entity, return back to an un-collapsed wavefunction?? It must do this, because if it didn't then every particle in the universe would surely have collapsed all wavefunctions into definitive states due to interactions, therefore quantum wierdness would have long dissapeared in the Universe.
If the answer is that after measuring, it returns to non-collapsed state, then surely measurement is just a snapshot, a still frame taken from a movie we dont understand. Or is it that taking the measurement, (still frame) changes the movie.
Anyway it seems to me that a measurement must be a snapshot of randomness. The idea that the wavefunction collapses (thus defined), seems silly as it must return back to an undefined state.
Ober
1 / 5 (5) May 14, 2013
Taking this idea further;
Consider an electron moving in straight line from a classical point of view. It's velocity could be determined by v = d/t. Any two snapshots of this electron would yield definitive predictive solutions to its locaion in the future. Now we know this is not the case for an electron in a quantum state. So what if we now assume that an electron in quantum state, does not exist in time. The equation v=d/t would yield a divide by zero. So perhaps a quantum state is an entity outside of time which is changing state at an infinte rate. Measurement gives you a snapshot (still frame) of an infintely changing state entity. The wavefuntion simply gives you all the states it COULD change to, and thus at infinte rate of change it appears to have all states until measured. Thus classical behaviour falls out, if an entity is repeatedly measured at a rate approaching infinity. The more frequent you measure the more classical it becomes and the more the entity appears in time.
vacuum-mechanics
1.1 / 5 (9) May 14, 2013
Corsin and Stephanie are keen to point out it's still not the whole answer to the big 'why' question: theories other than quantum physics, including classical physics, are compatible with the principle. But as researchers compile lists of principles that each rule out some theories to reach a set that singles out quantum physics, the principle of information gain versus disturbance seems like a good one to include.

Actually the 'why' question of 'physics' is the question about its working mechanism, such as in quantum physics which was born from the basic concept that electron particle can manifest as wave. So if we could understand why and how electron able to do something likes that, then that is the answer for the question….
http://www.vacuum...17〈=en
Ober
2 / 5 (7) May 14, 2013
Wandering even further through my crazy thoughts we get the following;
A black holes singularity is interpreted as mass with zero volume. Something we don't really understand. The singularity must have infinite density, and thus infinite gravity at that "point". Now consider trying to combine quantum mechanics with relativity, and again divide by zero's or inifities appear everywhere, and stop the convergence of these theories. I suspect that infinity is the key to the understanding here and that a result of inifinity does not suggest a failure of the combination of the two theories, but is actually correct, and showing us the true nature of the universe. So from this, it appears our concept of time needs re-evaluating. The odd behaviour/understanding comes from entities existing outisde of time. Of course I don't understand what outside of time really means, but my thought experiments seems to suggest this is a possibility. Classical behaviour is simply something existing in time.
Claudius
2 / 5 (10) May 14, 2013
So what if we now assume that an electron in quantum state, does not exist in time. The equation v=d/t would yield a divide by zero. So perhaps a quantum state is an entity outside of time which is changing state at an infinte rate.


If it is changing state, it is change per unit time, which means it is not outside of time. Or perhaps language is inadequate to describe this?

Ober
1 / 5 (4) May 14, 2013
Yes I realise the downfall of my language there Claudius. Perhaps a better term would be in a different time completely, one not related to our time as we know it. Also what is the unit of time, if it is changing at an infinite rate?? You see the definition of time breaks down, when infinity is introduced, and thats my point. Quantum behaviour could be from infinte internal change state, and classical behaviour is more evident in state change below infinity. Though some will argue that infinity - 1 is still infinity!!!! So perhaps the rate of change is either infinite in rate, or NOT. If NOT it is more and more classical, if it is then it is Quantum.

I must say your reply was very polite Claudius, so I don't know who gave you a ranking of 1. I will give you a 5 for being polite, and actually thinking about a difficult subject :-)
baudrunner
1.8 / 5 (10) May 14, 2013
If Erwin Schrödinger were alive today he would probably be embarrassed no end. The Schrödinger Cat's hypothesis is a lame and stupid attempt he made up to explain Heisenberg's uncertainty principle. I never did buy into it, and to my mind it does not explain the theory of quantum mechanics, but merely presents an explanation by example by way of a poor analogy. Better to just analogize using the discrete bands of frequency domains in the optical spectrum, or the discrete thermal energies required to effect separation of gases during the process of fractional distillation. The inability to measure both the exact position and momentum of a particle because of the mechanical effects of the measuring tools on the particle is pretty hard to explain away using Schrödinger's cat. I wish that everybody would just shut up about it.
DonGateley
1.4 / 5 (9) May 14, 2013
If the universe is a giant computer and what we are involved in is akin to a giant simulation then retaining causality to any scale whatsoever in a region would require infinite computing resources. To dodge that, quantum mechanics is then the "resolution" of the simulation where everything beneath a certain scale becomes part of the big monte carlo simulation which can remain finite on a region.

Just blathering, of course, but why not?
LarryD
2 / 5 (4) May 14, 2013
There are so many good points in the above comments and polite too. The thing that bothers me, not just with this article, but generally; is the quantum realm really discrete at any point at all? does the Universe really have any 'discreteness'? As a layman I read the articles and comments learning that there isn't any 'empty space' out there but 'a sea' [my word] of virtual particles, dark energy etc. and if one favors AWT then there is aether to consider too. Is the macro 'discreteness' just an optic illusion and that as we move along in time we re-new our structure continously?
Yet on the other side of the coin, we're told that at an atom is mostly 'empty space' and micrographic structure pictures would seem to support this; that is, definite shapes appear. So atoms would appear to be discrete. Are these really definite shapes of molecules etc or is what we see due to 'collapse'? Or is the 'empty space' filled with a Dark 'something'?
Then there is the 'many worlds' idea;
Howhot
4 / 5 (3) May 14, 2013
Here is something to perplex the mind; Where does Quantum Time fit into the nature of the quantum system? Does it dictate what is finely divided or probabilisticly fuzzy? I've always read many of the equations of QM as time dependent and with time being perfectly defined. I've always wondered if that was true.
eric96
1 / 5 (6) May 14, 2013
@hemitite

Yes.
Consider a black hole.
This would disturb the system without chance of observation.
A black hole is the ultimate particle accelerator, but rather than smash atoms into each other, it literally breaks them into their smallest constituents.
What a paradox that the natures deepest secrets are unobservable.
Clever God.
We see, but the beginning of the iceberg in quantum physics.
LarryD
1 / 5 (1) May 14, 2013
According to quantum theory it is possible that the cat is both dead and alive


It would have been more accurate to say "According to one interpretation of quantum theory..." In a many-worlds interpretation, the cat is not both alive and dead until the box is opened. The cat is alive in one world and dead in another, and you are merely finding out which world you are observing from when you open the box.

Hadn't thought of it that way before but one might grasp this better than that of superpositon in a single universe..assuming one can grasp a multiverse/extra dinensions in the first place! In such a place maybe G(m1m20/r^2) is G(a)(m1m2)/r^2+a), likewise for k(q1q2)/r^2.
Just a thought, that's all
clay_ferguson
1.9 / 5 (11) May 15, 2013
Like so many articles online these days there are a lot of words but nearly ZERO actual information. This article is garbage.
VendicarE
5 / 5 (3) May 15, 2013
"Would it be possible then to disturb a system without to some degree measuring it?" - hremitite

No. Measurement is interaction that imparts a change on the thing doing the measuring. and the thing being measure.

Measurement is a process of exchange. Be it charge, energy, momentum etc.

If you measure something you have acquired something from or given something to the thing being measured.
VendicarE
5 / 5 (1) May 15, 2013
"nearly ZERO actual information." - Clay

What you should have learned from this article is that measurement is interaction, and where no measurement is made there could have been no interaction.

This has been the standard working principle in QM for as long as I can remember.

VendicarE
5 / 5 (1) May 15, 2013
"Where does Quantum Time''" - Howhot

You presume that there is any such thing as quantum time.

Perhaps the best place to start would be the precise definition of what it is you mean when you use the word "time".

I await your definition.
VendicarE
5 / 5 (1) May 15, 2013
"is the quantum realm really discrete at any point at all?" - LarryD

If you mean physically discrete - I.E. belonging to only a volume that is a mathematical point, then the answer is no. There is always a spatial probability distribution in detecting a quantum object.

In many instances, the vocabulary used to describe quantum processes confused discreteness with stability

A particle like an electron exists only in environments where it's self interference produces an electron.

if an environment can not support the self interference of an electron to produce an electron, electrons are not found there.

Electrons entering such a volume stop being electrons and become something else.

VendicarE
5 / 5 (1) May 15, 2013
"The Schrödinger Cat's hypothesis is a lame and stupid attempt he made up to explain Heisenberg's uncertainty principle." - Baudrunner

If that is what you think, then you haven't thought deeply enough about the Cat's experiences in the box.

Think harder.
VendicarE
5 / 5 (1) May 15, 2013
'How does this collapsed wavefunction entity, return back to an un-collapsed wavefunction?" - Ober

It is always a wave function. It never stops being a wave function. The "collapse" refers to the selection of a single fourier component of the wave function that is one of the mathematically allowed solutions to the interaction.

The original wave function can always be represented by a fourier series of wave components. The "collapse" is the process of FILTERING out one of those components. Specifically, the one component that is STABLE for it's environment.

If there are no stable components, then there can be no "collapse", because it has no ability to be FILTERED by the environment.

VendicarE
5 / 5 (1) May 15, 2013
"when does weak measurement become destructive?" - kimmy

Week measurement is always weekly destructive.
VendicarE
5 / 5 (1) May 15, 2013
"the cat would be dead but its little cat spirit would still be alive somewhere in outer space" - Otto

Wrong. As the following video shows. Cat's have no souls.

http://www.youtub...UPLZdY-I
VendicarE
5 / 5 (4) May 15, 2013
"one can measure with ruler ,scale ,etc? without disturbance." - snoose

The photons of light that you use to illuminate the ruler and target altered their length.

You simply didn't notice it because of the fact that the things being measured were macroscopic.

The smaller you get, the more those pesky photons matter.

Eventually when you are measuring one photon with one electron or one electron with one photon, then the tools you are using to measure will dramatically alter the things you are observing.

thingumbobesquire
1.3 / 5 (8) May 15, 2013
Thought isn't a form of energy. So how on Earth can it change material processes? That question has still not been answered. Vernadsky
Blakut
1.7 / 5 (3) May 15, 2013
If you don't get any information from the system, how can you tell that you haven't disturbed it?
swordsman
1 / 5 (5) May 15, 2013
Physicists are just beginning to learn what engineers have known for decades, which is that there is no measurement that can be made without error. Now they need to work on a solution, just as engineers have done. By making enough measurements, you can characterize the system and gain knowledge as to the cause of the error and how to compensate for it.

To hell with the dead cat. He has also come and gone.
EyeNStein
1.8 / 5 (13) May 15, 2013
I'd be interested to see the schematics for your Heisenberg compensators (sic)
TheGhostofOtto1923
2.1 / 5 (15) May 15, 2013
The big debates of physics have always had a spiritual dimension.
From Einstein's "God does not play dice" to the huge row between Gamov and Hoyle over the big bang creation event.
Einstein was only being poetic. He never believed in any book god.
As ultimate physics becomes more uncertain and probabilistic; and every concrete classical concept like space and time becomes less invariant: Many will invoke or revoke God depending on their personal leanings
People do this because they want to live forever and they want their wishes granted and they will seize upon any unknown as direct evidence that the Creature who can give them these things does indeed exist.

Im sorry but this compulsion is pathological.
Myself I have no problem accepting that conscious life
Consciousness is not a 'thing'. Scientifically it is a worthless notion. People use it because it is a stand-in for the 'soul', as something which might possibly live forever.

You wont.
TheGhostofOtto1923
2.2 / 5 (13) May 15, 2013
"the cat would be dead but its little cat spirit would still be alive somewhere in outer space" - Otto

Wrong. As the following video shows. Cat's have no souls.

http://www.youtub...UPLZdY-I
Humans infected animals with souls when they started giving them names. 'Fluffy is going to heaven! I just know he is!'

You cant morally kill an animal with a name unless you are reasonably sure there is a heaven for them to go to. 'Dont cry sadie, bossie will be in heaven with all the other cows we've eaten.'

See how this works?
EyeNStein
1.5 / 5 (15) May 15, 2013
..or revoke God depending on their personal leanings

Hi Ghost. I wonder which side of the public God debate you stand on. You couldn't be a bigoted atheist,
without any humility
could you by any chance?
EyeNStein
1.8 / 5 (15) May 15, 2013
If consciousness doesn't exist there is a lot of brain research being wasted on this emergent phenomena.
http://phys.org/n...ess.html
EyeNStein
1.6 / 5 (14) May 15, 2013
"TheGhostofOtto1923" doesn't really exist: It's an AI computer simulation of a psychological model of repressed anger.
VendicarE
5 / 5 (1) May 15, 2013

"Thought isn't a form of energy. So how on Earth can it change material processes?" - thing

It can't, and it doesn't.

You are confusing observation with thought.

Observation = interaction.

When a photon interacts with an electron, it has "observed" the electron.

Observation = Interaction, and nothing more.
VendicarE
5 / 5 (1) May 15, 2013
"If you don't get any information from the system, how can you tell that you haven't disturbed it?" - Blakut

Since the state of the observer has not changed, it could have exchanged nothing with the particle it had the potential of observing.

If there is no exchange then there has been no exchange with the particle that could have been observed, and it's state remains unchanged.
VendicarE
5 / 5 (1) May 15, 2013
"Humans infected animals with souls when they started giving them names." - Otto

Which is why people often name their cats "cat" while dogs are always given real names.
emaalouf
3 / 5 (2) May 15, 2013
Bad example. The cat is not "quantum" object and does not comply with the superposition entropic principle.
sigfpe
5 / 5 (3) May 15, 2013
@snoosebaum If you use a ruler you need to look at the thing you're measuring. To look at it you need to bounce light off it. The more accurately you want to resolve it next to your ruler, the shorter the wavelength of light you need. The shorter the wavelength, the higher the energy of the photons and the more you disturb the subject. So it applies to rulers too.
VendicarE
3 / 5 (2) May 15, 2013
"If consciousness doesn't exist there is a lot of brain research being wasted on this emergent phenomena." - noEyenStein

You are confusing material existence with material organization.

TheGhostofOtto1923
1.7 / 5 (11) May 15, 2013
Hi Ghost. I wonder which side of the public God debate you stand on. You couldn't be a bigoted atheist...?
I only hate one more god than you do.
If consciousness doesn't exist there is a lot of brain research being wasted on this emergent phenomena
What 'emergent' 'phenomena' would that be?? You are apparently unaware of the 2 defs of the term. One is scientific:

"the quality or state of being aware of an external object or something within oneself"

-While the other is not:

"...the relationship between the mind and the world. To writers on spiritual or religious topics, it frequently connotes the relationship between the mind and God, or the relationship between the mind and deeper truths"

Your linked article was about cognition:

"Using a sophisticated imaging test to probe for higher-level cognitive functioning in severely brain-injured patients provides a window into consciousness"

-which has nothing to do with the spiritual crap you were referring to.
VendicarE
5 / 5 (1) May 15, 2013

"The cat is not "quantum" object and does not comply with the superposition entropic principle." - Emaalouf

Placed in a box, and isolated from the rest of the universe, it most certainly is a quantum object similar to a BEC and will obey all the rules of such macroscopic quantum objects.
VendicarE
5 / 5 (1) May 15, 2013
"Consider a black hole.
This would disturb the system without chance of observation." - Eric96

To an outside observer, nothing ever manages to pass over the event horizon of a BH, and hence nothing ever manages to find it's way inside, and thus it is always visible to the rest of the universe.

TheGhostofOtto1923
2 / 5 (12) May 15, 2013
@eyeNsty

Here is a guy who will tell you that consciousness is an illusion
http://www.ted.co...ess.html

-And he will also tell you that your god is an illusion:
http://www.youtub...;index=6

-and he is again, of course, correct. You should watch lots of his vids.
Silverhill
3.7 / 5 (3) May 15, 2013
@baudrunner
If Erwin Schrödinger were alive today he would probably be embarrassed no end. The Schrödinger Cat's hypothesis is a lame and stupid attempt he made up to explain Heisenberg's uncertainty principle.
Actually, Schrödinger made up his famous image to show what he thought of the superposition principle: that it was too silly to use.
Since a cat could not be both alive and dead, he argued, it made no sense to say that it -- and by extension, a quantum-level system -- would be in such a superposition. (He wasn't trying to support [or refute] Heisenberg there.)

@thingumbobesquire
Thought isn't a form of energy. So how on Earth can it change material processes?
Thought is patterned energy resulting from neurons' electrochemical processes. Energy can easily affect (and effect) material processes, as you demonstrate whenever you record a thought in the comments section.
EyeNStein
1.3 / 5 (14) May 15, 2013
Hi Ghost (if you exist?)
I only hate one more god than you do.

Now which of us is more rational: Myself who allows that consciousness could exist in other universes, or yourself who hates a god you don't think exists?
ValeriaT
1 / 5 (7) May 15, 2013
The consciousness has nothing to do with quantization of observable world, which existed way before you born or even before civilization evolved. Just because everybody believes, he's expert to consciousness, everyone here want's to talk about things, which (he believes) he understands. Sorry - but this article is not about what (you think) you understand. If you want to understand the things, you should think about it at the first line, not about something else. You should train the coherence of your thinking everywhere and not to distract the another people with your incoherent thinking, which is selfish and inconsiderate. If you don't know, what to say here about topic, don't say it here.
EyeNStein
1.6 / 5 (14) May 15, 2013
Hi Ghost
your god is an illusion

Which god would that be? I only cited an on going debate that discussions of ultimate physics often provoke. I can tell by the careful wording of your comments that you know Einstein did believe in a god ( where you attempted to imply that he did not.) I can also tell that you choose to discount the possibility.
I only suggested that humility and possibilities be allowed for.(As Einstein did )
Your scientific definition of conscious self awareness is fine with me. The last thing I want to suggest is that weird, spooky and impossible entities should be the god of any sane rational human being.
Rohitasch
1 / 5 (2) May 15, 2013
If consciousness doesn't exist there is a lot of brain research being wasted on this emergent phenomena.
http://phys.org/n...ess.html

"Emergent phenomena". You said it.
TheGhostofOtto1923
2.1 / 5 (14) May 15, 2013
Now which of us is more rational: Myself who allows that consciousness could exist in other universes, or yourself who hates a god you don't think exists
Me. I KNOW none of the book gods exist because of the judgement of innumerable scientists who have examined the evidence and concluded that the events described in said books, NEVER HAPPENED.

You conversely are willing to entertain notions of illusionary things in undocumented realms.

I respect evidence and the conclusions of pros who know how to analyse it. You entertain things in the absence of evidence, as if it were arbitrary. Its not.

And like rorschach points out, you like to use terms without knowing or caring what they mean...they just sound good.
TheGhostofOtto1923
2.1 / 5 (14) May 15, 2013
Einstein and god:

"It was, of course, a lie what you read about my religious convictions, a lie which is being systematically repeated. I do not believe in a personal God and I have never denied this but have expressed it clearly. If something is in me which can be called religious then it is the unbounded admiration for the structure of the world so far as our science can reveal it."

-You also dont care to look things up I see.
EyeNStein
1.6 / 5 (14) May 15, 2013
Oh look I can quote Wikipedia too:-
Einstein rejected the label atheist. Einstein stated: "I have repeatedly said that in my opinion the idea of a personal God is a childlike one. You may call me an agnostic, but I do not share the crusading spirit of the professional atheist whose fervor is mostly due to a painful act of liberation from the fetters of religious indoctrination received in youth. I prefer an attitude of humility. He said he believed in the "pantheistic" God of Baruch Spinoza.
EyeNStein
1.6 / 5 (13) May 15, 2013
So Darwin did, Feynman didn't and Einstein was a pantheistic-God believing agnostic??
What does that prove? Except there is a spectrum of answers in the debate.
I'm with Einstein in suggesting humility is preferable to dogma or ignorance.
vlaaing peerd
not rated yet May 16, 2013
"one can measure with ruler ,scale ,etc? without disturbance." - snoose

*cut*

Eventually when you are measuring one photon with one electron or one electron with one photon, then the tools you are using to measure will dramatically alter the things you are observing.


(To me) It still doesn't explain observation afterwards and conflicts with the notion of time in quantum physics. Like the sheet on which you shoot particles in the double slit experiment. Isn't observing the sheet after the shooting is done a measurement? If there is no "time" in QM, how can the outcome be different if the measurement is done afterwards?

btw, it's gingers that don't have a soul...gingers, not cats.
theon
1.3 / 5 (8) May 16, 2013
If a quantum measurement is carried out with a weak coupling to the apparatus, the off-diagonal ("cat") terms of the density matrix may still vanish, but no registration will happen. Hence the system is disturbed (by the interaction with the apparatus) but no information can be gained (in lack of a pointer indication). This poses a trouble for the employed fourth principle.
TheGhostofOtto1923
1.7 / 5 (12) May 16, 2013
So Darwin did, Feynman didn't and Einstein was a pantheistic-God believing agnostic??
What does that prove
It proves you're a bullshit artist. That is the value of evidence.
preferable to dogma or ignorance
-But you spout both. Einstein didn't believe in your god.
Kron
1.4 / 5 (10) May 16, 2013
You'll notice the cleverness of Einstein in his ability to answer his stance on God in an indiscriminate form. Pantheism is the belief in the equivalence of divinity (or God) and physical reality (or Universe).

The cleverness rests on this: if the Universe is intelligent, then we are a product of intelligent design; if, on the other hand, the Universe is unintelligent, then we are the product of unintelligent design.

Though, pantheism is a true religion, Einstein never regarded it as such. Einstein was an agnostic. Agnostics believe (and don't believe) only that which can be proven (like with empirical evidence).

That's the cleverness. Whether the Universe is intelligent or not, Einstein is correct. We are the product of the Universe.
vlaaing peerd
not rated yet May 16, 2013
Agnostics believe (and don't believe) only that which can be proven (like with empirical evidence).

That's the cleverness. Whether the Universe is intelligent or not, Einstein is correct. We are the product of the Universe.


yea agnostics have a tendency to avoid semi dead cats. Can we now get back to the subject?
drhoo
5 / 5 (1) May 16, 2013
Henry P Stapp believes your mind actually modifies the universe when you look upon it, as far as I can tell from his writings.

And he is not crank

http://en.wikiped...ry_Stapp
EyeNStein
1.3 / 5 (12) May 16, 2013
The researchers assume the system is not evolving in time

Thus assumption violates both special relativity where movement at c in spacetime is assumed and the Quantum decoherence principle where the wavefunction doesn't go away (collapse) it continues but just stops being coherent (i.e. capable of wave interference with its other possible selves in space.) http://en.wikiped...oherence
That darn cat is the worst possible example to base any new theory of reality on.
Stephen_Crowley
1 / 5 (8) May 16, 2013
To "understand infinity" is incredibly naive, https://en.wikipe...Infinity here is an example.... 1 2 3 4 5 ... and 2 4 6 8 10 ... the latter sequence is clearly "larger" than the "first" ..
Yes I realise the downfall of my language there Claudius. Perhaps a better term would be in a different time completely, one not related to our time as we know it. Also what is the unit of time, if it is changing at an infinite rate?? You see the definition of time breaks down, when infinity is introduced, and thats my point. Quantum behaviour could be from infinte internal change state, and classical behaviour is more evident in state change below infinity. Though some will argue that infinity - 1 is still infinity!!!! So perhaps the rate of change is either infinite in rate, or NOT. If NOT it is more and more classical, if it is then it is Quantum.
I must say your reply was very polite Claudius, so I don't know who gave you a ranking of 1. I will give you a 5 for being polite,
Stephen_Crowley
1 / 5 (8) May 16, 2013
And anyway, I kindly redirect you guys over to Matti's blog, where he has some extremely well-developed ideas on this subject, m a t p i t k a . b l o g s p o t . c o m/ but I'm sure some group or another will start shouting crackpot at one or the other...
JIMBO
1 / 5 (4) May 18, 2013
Bottom Line: Its Math, not physics. The argument for a discrete Hilbert space, which they claim their result refutes, is solidly based upon the existence of the Planck scale.
ValeriaT
1 / 5 (7) May 18, 2013
In dense aether model the Universe is random and we are random portion (Boltzmann brains) of it. These two random objects overlap at two dimensional scales (extrinsic and intrinsic ones), where their randomness compensates mutually. As the result, the otherwise random Universe appears strikingly symmetrical at these dimensional scales and it appears being composed of spheres there. And this is just the scope, where the mass and energy exchange are getting quantized too. At the scope of atoms the energy is quantized, at the scope of stars (which are composed of mostly atoms) the mass is quantized. Outside of these two scales the quantization of observable reality is less or more violated on behalf of random / hyperdimensional model. Even the heaviest particles aren't quantized - they do exhibit many energetic states in similar way like multiparticle systems of classical world. It would be therefore mistake to believe, that the quantization is intrinsic property of observable reality.
Bombayrefugee
1 / 5 (1) May 19, 2013

@Eikka

Where in fact the cat is just as valid an observer of the device going off as the person opening the box.


So are every air molecule in the box besides the cat. You're confusing observing with concious observing, when it really means just propagation of effects from causes.

Outside of the box, the scientist has not yet felt the effects of the cat being dead..."

Funny. The cat may not be a physicist, but he is probably qualified to observe whether he's dead or not.
EyeNStein
1.3 / 5 (12) May 19, 2013
@Eikka
If you are going to propagate this atom decay effect to the cat, through the observer up to their supervisior, then you end up with multiple information realities which only converge once everyone has been told.
This is about as plausible as saying a tree makes no sound falling if no one listens.
There is only one reality, one system, formed by the intersections of all the wavefunctions of all the particles. This is the quantum decoherence principle/theory as we currently understand it. See:- http://en.wikiped...oherence
In the double slit experiment: Once measured, a photon is in fact decoherent with itself regardless of whether the president has been told yet.
Taking that darn cat experiment literally is only for confused folk.
Kron
1.4 / 5 (11) May 19, 2013
The probability of 7 billion self-aware entities (all with false syncronized memories) condensed out of fluctuations in an Earth sized volume, in a Universe the size of the Observed, is nearly zero.

The Boltzmann brain being the observable Universe itself in an infinite sea of possibilities (infinite fluctuating volume), is a more probable case than a single Big Bang fluctuation. The ordered structure of the Universe seemingly violates thermodynamics, but in an infinite Universe, a region where entropy works in reverse isn't as unlikely.

The infinite Universe is on the most part unaware of itself, but every so often a region of awareness condenses. Our observable nook contains self aware entities, but to call ourselves "Boltzmanns" would be unfitting. If anything, we are subsets of the Boltzmann itself. The Observable Universe is the Boltzmann brain, we are its thoughts.
EyeNStein
1.6 / 5 (13) May 19, 2013
i'll have a shot of whatever he's having. Anyone got a cigarete lighter.
mohammadshafiq_khan_1
May 20, 2013
This comment has been removed by a moderator.
beleg
1 / 5 (5) May 21, 2013
In all probability an unchanged state is equivalent to an independent event.
Silverhill
5 / 5 (2) May 23, 2013
Einstein's space-time concept has been mathematically, theoretically & experimentally proved baseless and General Theory of Relativity ... also has been proved baseless
That's why the GPS satellite timing signals need no corrections based on their speed w.r.t the ground (Special Relativity) and their height above the ground (General Relativity), eh?